<?php
// 定义变量并默认设置为空值
$nameErr = $emailErr = $getderErr = $websiteErr = "";
$name = $email = $gender = $comment = $website = "";

if ($_SERVER["REQUEST_METHOD"] == "POST"){
    if (empty($_POST["name"])){
        $nameErr = "名字是必须的";
    }
    else
    {
        $name = test_input($_POST["name"]);
        // 检测名字是否只包含字母跟空格
        if(!preg_match("/^[a-zA-Z]*$/",$name)){
            $nameErr = "只允许字母和空格";
        }
    }

    if(empty($_POST["email"])){
        $emailErr = "邮箱是必须的";
    }else{
        $email = test_input($_POST["email"]);
        // 检测邮箱是否合法
        if (!preg_match("/([\w\-]+\@[\w\-]+\.[\w\-]+)/",$email))
        {
            $emailErr = "非法邮箱格式";
        }
    }

    if (empty($_POST["website"])){
        $website = "";
    }
    else{
        $website = test_input($_POST["website"]);
        //检测 URL 地址是否合法
        if(!preg_match("/\b(?:(?:https?|ftp):\/\/|www\.)
        [-a-z0-9+&@#\/%?=~_|!:,.;]*[-a-z0-9+&@#\/%=~_|]/i",$website)){
            $websiteErr = "非法的 URL 的地址";
        }
    }

    if(empty($_POST["comment"])){
        $comment = "";
    }
    else
    {
        $comment = test_input($_POST["comment"]);
    }

    if(empty($_POST["gender"])){
        $genderErr = "性别是必需的";
    }else{
        $gender = test_input($_POST["gender"]);
    }
}

function test_input($data){
    $data = trim($data);
    $data = stripslashes($data);
    $data = htmlspecialchars($data);
    return $data;
}
?>